Abstract: A catalytic component for olefin polymerization, produced by a process which comprises causing (A) magnesium metal, (B) a halogenated hydrocarbon represented by the general formula, RX [wherein R stands for an alkyl group, an aryl group, or a cycloalkyl group each having 1 to 20 carbon atoms and X for a halogen atom], and (C) a compound represented by the general formula, X.sub.n.sup.1 M(OR.sup.1).sub.m-n [wherein X.sup.1 stands for a hydrogen atom, a halogen atom, or a hydrocarbon group having 1 to 20 carbon atoms, M for a boron, carbon, aluminum, silicon, or phorphorus atom, R.sup.1 stands for a hydrocarbon group having 1 to 20 carbon atoms, m for the valency of M, and m>n.gtoreq.